


(Don't) Be Still My Beating Heart

by BlackKittens



Category: Big Hero 6 (2014), Big Hero 6: The Series (Cartoon)
Genre: Fluff, Kissing, Sweet
Language: English
Status: Completed
Published: 2019-09-06
Updated: 2019-09-06
Packaged: 2020-10-11 01:23:24
Rating: Teen And Up Audiences
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 1,387
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/20537858
Author URL: https://archiveofourown.org/users/BlackKittens/pseuds/BlackKittens
Summary: Trina didn't have a beating heart in her robotic body, but Hiro never failed to make it pound anyway.





	(Don't) Be Still My Beating Heart

**Author's Note:**

> As usual, everything post-season one of the cartoon is dead; my headcanons and fanon are law here.
> 
> Since I already struggle writing romance, and this is the youngest ship I currently have, I started thinking back to when I was fourteen and in my first relationship for inspiration. I remember being infatuated with kissing, so this is kind of based on that. I also decided to keep Trina a robot here because I'd thought it be more interesting describing a robot's experience than a human's.
> 
> By the way, I recently found a really cool prompt list whose fluff section gives me Hirina ideas, so between my other WIPs, I'm going to do my best to challenge myself to write as many of them as I can (there's 50 total). I figure it'll be fun! This fic here isn't part of the list; I'm just letting you know a lot more Hirina is likely to come this fall/winter. :) Some will be AUs, some will be aged up, some will likely connect to each other (I might put those in a series), but all should be oneshots. (I'm still working on my longer/multi-chapter Hirina ideas, and I don't need to add 50 more to the list. xD)
> 
> Anyway, I hope you enjoy this quick oneshot!

Trina didn't have a physically beating heart in her body; it came with the territory of being a robot. What she did have, however, was an AI that was irritatingly accurate to that of a human brain, and for whatever reason, that AI sometimes got the idea she did in fact have internal organs and therefore responded accordingly in certain situations. Emotional situations, more often than not. Sometimes physical ones. If she was injured, she could feel pain; if she was devastatingly upset, she could feel faint or nauseas; if she was nervous, flustered, and stupidly happy, then her non-existent heart could suddenly pound in her chest. Right now, she was experiencing the last one.

It was Hiro's fault - not that she would hold it against him. He had a very kissable face, and Trina could hardly begrudge him that.

They were hiding in the garage, both doors shut tight, away from any prying eyes or smirking faces. They didn't want to be found again, by Hiro's friends or family; the last time they were caught making out, Wasabi had made a bigger, way too overdramatic deal out of catching the couple lip-locked than either of them thought necessary - even the others thought so, with Gogo and Aunt Cass forcibly dragging the stuck-stammering-apologies dude away. He later explained that he saw Hiro as a younger brother of sorts (their whole gang did) and therefore it was extra embarrassing to stumble upon the couple during a private moment. (Gee, wonder how she and Hiro had felt). They even locked the outer door to prevent a repeat of the event.

Perched on the couch, Trina had her hands on Hiro's thin shoulders, while his hands were wrapped around her lower back, covering the edge of her shirt and the free strip of skin below it. It sent tiny, delightful shocks up her spine, which she was sure was just her AI acting up again.

Their kisses had been clumsy and hesitant when they first got together. They'd both been red as tomatoes, unsure of what to do with their hands, and clueless as to how long a kiss should last. Trina believed they had it down pat now. What was important was that kissing was fun, and honestly? If she could, she'd kiss Hiro all day. She was pretty certain he felt the same way. That was one nice thing about her AI replicating a human's to a T, she supposed; Trina had no hormones running through her circuits, yet she was just as drawn to him as he was to her. It was a shame they couldn't spend all day every day kissing. Hiro's lips were soft, sometimes chapped, and Trina loved how they fit against hers.

Breathing through his nose, Hiro tilted his head and deepened the kiss.

Another delighted spark shot up Trina's spine. Her heart pounded faster - or so her AI told her it thought it was. If she didn't know any better, she would have believed the _thump, thump, thump_ she felt in there was real. But she knew if she put her hand there, there would be nothing beating beneath her fingers. Still, Hiro had gotten it going faster, and Trina found herself sighing against his mouth.

One of her hands lowered from his shoulder down to his side as she pushed herself closer to him. Hiro responded by releasing his own sigh.

Trina grinned into the kiss. It was almost funny how they sort of melted into each other when they kissed. The need to be closer, as close as they could get, and push even closer when they realized what they already had still wasn't enough. She'd never felt anything like this with anyone else.

Then again, Hiro was her first crush as well as her first boyfriend. Trina guessed it was to be expected he was the only one she'd felt this way towards so far.

To her disgruntlement, though, that was when Hiro pulled back.

"What?" Trina asked.

"I just need to breath for a second," he replied, wearing a little smirk at her.

Her disgruntlement faded; Trina burst into giggles.

Hiro's smirk faded. "What?"

She a put hand on her chest, falling back on the back cushions some. "My lipstick! We forgot about my lipstick again!"

This got her every time.

Hiro jerked his head in bewilderment, and brought a hand up to his mouth. Her pink lipstick was smeared over his lips and surrounding skin, and all his fingers did was smear it further.

He let out his own laugh. "Oh geeze; again?" Hiro peered closely at her face and laughed louder. "Yup, yours is smudged, too!"

Trina had to resist the urge to touch her mouth; she didn't want lipstick on her fingers. "I can't believe we forgot again!"

Hiro jumped up to get the paper towels he and his brother kept stocked in one of the garage cabinets. "We really need to start remembering! One of these days we're gonna forget for so long that I want into the café covered in it."

"Heh!" Trina bit the inside of her cheek. "Actually, I'd love that - everyone would know you're mine."

Hiro froze mid-reach for the paper towels. His cheeks flushed.

Something about that, as well as seriously imagining her joke in action, made her own face warm. Trina felt her heart pound even faster.

Hiro was hers, wasn't he? The same way she was his. It was utterly sappy, and she internally scoffed at herself for it, but still her heart ran. They were each other's.

"Eh," Hiro retracted his arm and closed the cabinet empty-handed.

Trina watched him curiously.

He returned to the couch, leaping on it and landing quite close to her. "I'm just gonna get more on my face when we start making out again. Yours'll smudge more, too. Let's save the cleaning for later."

She chuckled at that. Wrapping her arms behind his neck, she said, "Okay," and just like that, they were back to kissing.

Apparently, her mind wasn't done being sappy, because as they continued, Trina got to thinking about how lucky she was.

Her father had told her all her life that no one would accept her as a person if they found out she was a robot (his way of keeping her from revealing herself in public), and once he discovered her old crush that had returned to bot-fighting was the same boy he wanted for an apprentice, reminded her that it would only be in his new world that someone like Hiro would come around to someone as ahead of their time as her.

His new world hadn't come, though, and it still hurt to think about her father as gone, but he'd been wrong (Trina refused to ponder whether he'd been lying or sincerely believed it himself). Hiro had genuinely believed in her, and without that, she doubted she'd be here today. She had no idea where she'd be. And he not only still saw her as a person, not a mindless machine, his feelings for her hadn't changed upon the discovery. It had taken some getting used to was all. She was incredibly lucky to have him.

His fingers found the free strip of her back, sending more tingles up her spine.

Trina was now the one who pulled back, a small, breathy laugh on her lips, and ducked her head into the junction between his shoulder and neck. She simply laid there, content.

Hiro started, surprised. "You okay?"

"'Course, genius," she teased. "I'm just happy is it."

"Happy?" His hands adjusted to clasp around her back, hugging her. "Oh. Okay. I'm happy, too," he ended with a chuckle.

Trina felt his chin settle on top of her head, and her heart pounded so hard that she would have thought it was about to break out of her chest. In a good way.

It was a difference. Normally she hated when her AI got the notion she had an entirely organic body. She hated pain, she hated light-headedness and nausea, and she hated when she got worked up to the point one of her few biological functions started (like crying; why her father gave her real tear ducts, she didn't know). But this was good. This, she liked. This, she wouldn't mind feeling forever.

**Author's Note:**

> I headcanon that Obake built Trina as the child he wanted, and he built her to be as a human as possible.
> 
> Her AI is amazingly advanced and designed to mimic a human brain to a T, from childhood to adulthood. That's why she can think and feel of her own accord, and isn't closer to, say, Baymax, in terms of personality and reactions. It's so close, however, that it also mimics the parts of the brain "aware" of the physical body and in charge of physical reactions, if that makes sense?
> 
> In the case of the tear ducts, Trina was built as a robot who could grow up (if the show can have the periodic table forming Globby, I can have a robot built to grow,) and she was allowed to venture outside; if, say, as a little kid she went out into San Fransokyo and fell and starting crying like kids do, but there were no tears, you'd think there was something wrong, right? Not immediately assume she's a robot, of course, but what's with the kid's eyes??? Do they need to see a doctor or something??? I imagine Obake wanted to cover all his bases, no matter how small.
> 
> Like I said, more Hirina coming up in the future! My oneshots prompts and a few longer projects are down the road!


End file.
